So in the 1840's farming required A LOT of people to do work (slavery). How come they didn't need as many people in 1940?

Well, the correct answer is to reduce federal spendingthis is because he had done a reconstruction of the system to improve it for the future of the united states, but it didn't reduce federal spending pretty much at all. the previous governments made federal spending a huge problem causing the promise to fail because it was pretty much an impossible  task.i hope this mark me as brainiest